1. Field of the Invention
The present invention relates to information processing technology, for example, a technology effective when applied to debug, performance measurement and the like in the development process, maintenance process and the like of an information processing device.
2. Description of the Related Arts
For example, in the development and maintenance processes of an information processing device, it is necessary to debug in order to trace the cause of an abnormal operation or a failure, to improve performance or the like.
Therefore, history memory for recording an operation history can be provided in a plurality of devices constituting a system, an operation history during a specific period before and after a failure occurs can be recorded by instructing each device to simultaneously start and stop recording an operation history from outside. Then the history can be read out to the outside and can be used to analyze a cause.
Performance can be also measured by recording the amount of transferred data and the times of specific executed instructions in a specific period in each device, in history memory as an operation history.
In this way, as a method for giving instructions on various operation timings and the like to each device from outside, traditionally a dedicated signal wire is installed.
It is because the debug function of hardware, such as history memory and the like can be used without disturbing an operation at the time of normal running and accurate failure analysis reflecting an actual operational state is possible.
However, since today the integration density of semi-conductor devices constituting a device is improved, and the mounting cost of signal wires between devices becomes relatively high and is increasing, a cost for installing a dedicated debug signal wire, which is not used at all in a normal operation, between devices cannot be neglected.
A control command to control a debug function can be also added instead of installing the dedicated debug signal wire as this countermeasure. However, in this case, the normal running operation of the system is disturbed by the execution of this control command and it becomes disadvantageous when analyzing a system behavior highly depending on an operational timing.